Apparatus for efficiently burning fluid fuels



Aug. 13, 1935, L. c. HUFF APPARATUS FOR EFFICIENTLY BURNING FLUID FUELSFiled April 28, 1930 NN @NNW N 1 if L Patented Aug. 13, 1935 UNITEDSTATES APPARATUS FOR EFFICIENTLY BURNING FLUID FUELS Lyman C. Huff,Winnetka, Ill.

Application April 28, 1930, ,Serial No. 447,987

1 Claim.

This invention relates to a means and method of burning combustible gas,and refers more specically to the eiiicient burning of gas as a fuel indomestic and industrial furnaces or the like.

The utility of the invention, as well as the objects and advantagesthereof, will be apparent from the accompanying drawing and followingdetail description.

In the single drawing, a vertical sectional elevation is shownillustrating suitable instrumentalities for carrying out my invention.

Referring in detail to the drawing, I indicates a lower header of aconventional furnace which may be annular in shape and may be of anyconventional type. A plurality of tubes 2 may connect into the upperportion of said header and may be connected at their opposite upper endsto a similar header (not shown). It is to be understood, of course, thatthe type of furnace in which my invention is to be used is immaterialand may take the form of a steam, hot water, vapor, hot air furnace, orthe like.

A plate 3 may be enclosed Within the header I and may be supported bybrackets or angle irons 4. Plate 3 may be provided with a series ofcircularly disposed apertures 5 and a similar series of apertures 6. Aplurality of radially extending bars 1 may be supported beneath plate l3by means of bolts 8 and 9, said bars being spaced from plate 3 by meansof collars or spacers I and Il, respectively. A shutter or damper I2 ofcircular shape may be slidably positioned between the bolts 8 and 9 andmay be interposed between the bar 1 and plate 3, said shutter beingprovided with a series of apertures I3 which may be adapted to registerwith the apertures in the plate 3. I

To facilitate'the movement of shutter I2 and hence control the degree ofregistration between the apertures 5v in the plate 3 and apertures 3 inthe shutter I2, a handle I4 may be provided upon the lower surface ofshutter I2. A circular shutter I5 may be positioned beneath apertures 6and may be provided with a series of apertures I6 which may be adapted`to register with apertures 6 upon circular movement of the shutter I5within the space between plate 3 and bar 1. To facilitate this movement,a handle I1 may depend from the lower surface of shutter l5.

It is to be understood, of course, that although slidable shutters ordampers are shown for controlling the opening and closing of apertures 5and 6, the invention in its broadest concept contemplates the use of anysuitable type dampers.

A hearth I8 of heat radiating material may be positioned upon the upper-surface of plate 3, the outer surface of which may follow the contourof header I. The hearth I8 may be divided into two sections, an outervannular portion I9 and an inner portion 20, said portions being sospaced from each other as to provide an annular fissure 2|. The innerportion 20 of the hearth may be provided with an opening 22 at itscenter which may connect at its lower end with the apertures 6 in theplate 3. The upper edge of the opening 22 may be rounded as shown at 23to define a more or less crater-like opening.

A mixing chamber 24 may be co-axially positioned within opening 22 andmay be' provided internally at its lower end with a Venturi neck 25. Theelement 26 forming said Venturi neck may be removably positioned withinthe chamber 24 by means of set screw 21 or other suitable fasteningmeans. An air chamber 28 may be threadedly mounted on the lower end ofmixing chamber 24 and may be provided at its lower end with a plate 29,said plate being threadedly engaged upon the inner surface of chamber28. The plate 29 may be provided with a plurality of circularly disposedapertures 30 and may support at its center an upwardly extending nozzle3|. l A shutter 32 may be positioned immediately adjacent the lowersurface of plate 29 and may be maintained in operative slidable positionby means of nut 33. The shutter 32 may be provided with a series ofapertures 34 which are adapted to be brought into or out of registrationwith apertures 30 by the rotation of shutter 32. To facilitate saidmovement, a handle 35 may be mounted upon movable shutter 32. 'I'helower end of nozzle 3| may be connected by means of elbow 36 to fuelintake pipe 31.

A cap 38 may be threadedly mounted upon the upper end of mixing chamber24 and may be provided with a plurality of laterally disposed aper- 40tures 39. A hood 4U may be mounted upon the cap 38 by means of bolt 4|and may be spaced therefrom by collar 42. The hood 40 may be providedwith a plurality of openings I3, the purpose of which will behereinafter more fullyl described.

In carrying out my invention a uid fuel, such as, for example, the usualcommercial illumina-tling or heating gas, may be introduced through pipe31 and may be discharged through nozzle 3| into the Venturi neck 25. Dueto the fact that the gas under pressure is passing through a more orless restricted opening, an inducing action will take place which willdraw air through openings 3l and 30 into air chamber 28 and thence intochamber 24 where the induced air and combustion gas will mix. Themixture will then be discharged through apertures 39 and is passingbetween the rounded defining edge 23 of aperture 22 and the ou-tercurved edge 44 of hood 40, a secondary supply loi' air will be drawnthrough apertures I6 in shutter I5, apertures 6 in plate 3 throughopening 22, and will mix with said discharged gas and tend to produce amore eilicient combustion of the mixture issuing from aper- -tures 39.

It can readily be seen that as the combustible mixture issuing fromapertures 39 is ignited, the heat radiating material 20 will becomehighly heated and will give off a great amount of radiant heat and, inaddition, due to the peculiar character of the space 45 provided betweenthe rounded edge 23 of the hearth 20 and the lower curved edge 44 of thehood 40, a zone of reduced pressure will exist beneath hood 40. This, ascan readily be seen, will tend to induce a recirculation of the gasesissuing from the apertures 39 through apertures 43, as shown by thearrows at 46. In this manner, the freshly introduced mixture issuingfrom apertures 39 will be heated both by contact with the hearth 20 andby the recirculation of the heated combustion gases 46 passing throughapertures 43.

By diluting the freshly admitted gas with recirculated hot gasescombustion will take place gradually and the noise of combustion will begreatly diminished. The character of the flame can also be controlled bythe amount of hot gases recirculated and a highly luminous or radiantflame may be obtained. By recirculating hot gases in this manner anyincompletely burned fuel will again be brought in contact with air in ahigh temperature zone and complete combustion will be eifected. It isobvious that inasmuch as the air passing through apertures I6 and 6 andspace 22 must travel adjacent the hot hearth 20, the same will becomepreheated and will tend to further cause eicient combustiom o Aplurality of upwardly extending projections 41 may be provided upon theupper surfacesof hearths 20 and I9 and tend to impede or divert thegases passing adjacent the upper surfaces thereof, causing said gases toeddy and be main- .tained in contact with the upper surfaces of saidhearths. In this manner a greater areaof radiant iiame will be provided.

As the hot gases of combustion pass the upper end of fissure 2 I, airwill be induced through said iissure and will mix with said gases ofcombustion and tend to form a more radiant name.

To control the character oi' theiame caused by the ignition of the gasesissuing from apertures 39, the air brought into mixture with said gasesmay be regulated initiallyby the degree of registration of the apertures34 and 30, and thereafter additional quantities of air may be broughtinto contact with the ignited mixture by controlling the degree ofregistration of apertures I6 and 6, and also the degree of registrat1onof apertures I3 and 5. In this manner, a close control may be maintainedupon 'the character of flame produced.

If desired, the metal portions of my device which may be subjected, tohigh temperatures, for instance, hood 40, cap 38, spacer 42, bolt 4I,etc., may be constructed of a metal having high heatresistingproperties. Also, if desired, a heat insulating medium, such as asbestosor the like, may

separate plate 3 from refractories I9 and 20, as, .26

shown best at 48.

It is to be understood, of course, that instead-' of relying uponinducing means for supplying air,

a blower (not shown)v may be utilized to supply said air. And, ifdesired, the heat radiating hearths I9 and 20 may be dispensed with, andan annular member (not shown) may take the place of the rounded definingedge 23.

I claim as my invention:

In combination, means forming a primary air supply chamber and a mixingchamber connected thereto, a fuel supply pipe extending into said airchamber to discharge fuel under pressure into said mixing chamber and tothereby induce a ilow of air into said mixing chamber from said airchamber, an annular heat radiating hearth surrounding said mixingchamber and forming therewith an annular secondary air chamber, aperipherally apertured distributing cap closing said mixing chamber,apertured hood means mounted above said cap and coacting with theadjacent edge of said hearth to form an annular opening through whichthe mixture of fuel and air from said cap is discharged across saidsecondary air chamber and directly over and in contact with the uppersurface of said hearth, whereby secondary air and products of combustionwill be entrained into the said mixture prior to its discharge throughsaid annular opening, and a second annular hearth spaced from andsurrounding said rst hearth to form therebetween a tertiary air supplychamber through which additional air may be supplied.

' LYMAN C. HUFF.

